He's one of the most accomplished and prominent astronauts from the last 25 years and after an illustrious career Mark Kelly has decided to hang up his spacesuit for good.

Kelly, a long time NASA astronaut, said in an interview with The Arizona Republic he's retiring from military and space travel effective on October 1st of this year. He wants to focus on helping his wife, Congresswoman Gabrielle Giffords, recover and work on her memoir. Giffords was shot in the head in January and was nearly killed by a would-be assassin. She has since been on the path to recovery, currently at the TIRR Memorial Hermann rehab hospital in Houston.

Kelly was a veteran of the Navy for 25 years after graduating from the U.S. Merchant Marine Academy in 1986. He flew 39 missions as part of Operation Desert Storm and received a degree in aeronautical engineering from the U.S. Naval Postgraduate School. Since 1996, he has been a NASA astronaut. The well accomplished Kelly has been on four space shuttle missions, including most recently the final mission for the Endeavour shuttle.

Overall, Kelly has logged 38 days in space. His brother Scott is also an astronaut for NASA.

Kelly said leaving NASA will be hard and he's been a bit apprehensive about it, but he realizes it's time for him to do other things. Most prominently this involves his family. Kelly has two daughters from an earlier marriage as well as Giffords to take care of.

As mentioned, Kelly will also work on Giffords' memoir with Giffords herself and Jeffrey Zaslow, a Wall St. Journal columnist. Giffords will contribute more as she gets better. The book will be published by Simon & Schuster's imprint Scribner. Neither Kelly or Giffords will get an advance on the book but could collect royalties. Kelly said their plan is to donate much of the proceeds to charity. The book will be reviewed by the House Ethics Committee as per the rules of congress.

Kelly's departure comes at a time of great upheaval for NASA in regards to space travel. After next month's final Atlantis mission, the space shuttle program will end for good. Following this, NASA will push to help create privately run space missions.

I know that as our space program evolves, there are those who will question NASA's future. I am not among them. There isn't a group more dedicated to its mission or more capable than the outstanding men and women of NASA. Exploration is a critical component of what makes our country great. We will continue to explore and NASA will continue to lead that effort, Kelly has said.

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